In a known airbag sensor attachment structure, a crash box (referred to below as a “bumper beam extension”) is provided at a front end portion of a front side frame, and an airbag sensor is attached to a front wall of the bumper beam extension inside the bumper beam extension (for example, see Japanese Unexamined Patent Application Publication No. 5-112195).
In the airbag sensor attachment structure in Japanese Unexamined Patent Application Publication No. 5-112195, the airbag sensor is housed inside the bumper beam extension, thereby enabling working space to be secured for assembly of a bumper beam or the like to a front end portion of the front side frame.
Moreover, in a full overlap frontal collision or an offset collision, for example, the bumper beam extension undergoes compression (namely, axial crushing), and the airbag sensor moves toward the vehicle body rear. This enables detection of the full overlap frontal collision or the offset collision by the airbag sensor.
However, in the airbag sensor attachment structure in Japanese Unexamined Patent Application Publication No. 5-112195, the airbag sensor is housed inside the bumper beam extension. Accordingly, the full overlap frontal collision or offset collision cannot be detected by the airbag sensor until the bumper beam extension has been compressed. It is therefore difficult for the airbag sensor to detect a collision at an early stage, during an initial stage of a full overlap frontal collision or offset collision.
In another known airbag sensor attachment structure, a flange of a bumper beam extension is provided to a flange at a front end portion of a front side frame, and an airbag sensor is attached to the flange of the bumper beam extension (see, for example, Japanese Patent No. 3690232).
In the airbag sensor attachment structure of Japanese Patent No. 3690232, in a full overlap frontal collision or an offset collision, for example, the bumper beam extension is compressed, enabling detection of the full overlap frontal collision or the offset collision by the airbag sensor.
However, in the airbag sensor attachment structure of Japanese Patent No. 3690232, the airbag sensor is attached to the flange of the bumper beam extension (namely, a base portion of the bumper beam extension). It is accordingly difficult for the airbag sensor to detect a collision at an early stage during an initial stage of a full overlap frontal collision or offset collision.